1. Field of the Invention
The present invention relates in general to an image processing apparatus including an image reading device operable to read an image on an original, and a method of setting an image reading area of the image reading device.
2. Discussion of Related Art
A known facsimile apparatus equipped with an original platen and having a copying function is arranged to first detect a size of an original placed on an original platen, by performing a pre-scanning operation or by using an original-size sensor, and then read the image on the original according to the detected size of the original, to transmit image information representative of the read image to an external device.
Where the size of the original is detected by performing the pre-scanning operation, the operation to read the image is performed after the pre-scanning operation, so that the facsimile transmission requires a comparatively long time. Where the size of the original is detected with the original-size sensor, without performing the pre-scanning operation, the provision of the original-size sensor increases the cost of manufacture of the facsimile apparatus. To eliminate those drawbacks, there has been proposed an inexpensive, simple facsimile apparatus arranged to efficiently read the image on the original, by reading an entire reading area of the original platen, without detecting the size of the original by the pre-scanning operation or the original-size sensor. The assignee of the present application has manufactured one example of such a facsimile apparatus, which is a multiple-function apparatus commercially available under the trade names “MFC-9700” and “MFC-9800”.
On the other hand, there has been developed a facsimile apparatus equipped with an original platen the reading area of which has a large size to meet a recent demand of the users for increasing the maximum size of the original that can be placed on the original platen. The original has different sizes such as a letter size and a legal size. The letter size and the legal size have the same width dimension and different length dimensions.
When an image carried by an original whose width dimension is smaller than that of the originals of the letter and legal sizes is transmitted by the facsimile apparatus arranged to read the entire reading area of the original platen, as described above, any image if present outside the original is undesirably read, since the reading area of the original platen is larger than the entire surface area of the original. In this case, the image received by an external facsimile apparatus of the receiver from the facsimile apparatus of the transmitter in question is undesirably reduced in size and tends to have reduced legibility by the receiver.